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wintersynth brings us a story about a group of enthusiasts who made a catapult out of a 2,800lb industrial robot arm. They used it to launch bowling balls, fireballs, and cans of beer toward a stationary target, and they controlled the catapult's aim with a graphical UI on a laptop.
"I wanted to be able to control the rotation of the robot so we could aim the robot from the laptop, but I quickly realized that since the desert is so flat, we could do some basic ranging on the target too. I also wanted the targeting to be overlaid in 3d over a photograph of the target area. The software needed to control the robot like an MMO or RTS game. I suspect that video games, in general, have some of the most optimal control interfaces. I wanted to try a control scheme similar to the area effect spell targeting in World of Warcraft."

I'm sure with a Class III license you might have a shot at finding one, if you can pony up the cash to buy one (Are they even legal to import? I'm too lazy to look it up.) I'm happy with my 17, however.:D

It's not even that bad. There's no need to get a license of any sort. Here's what you need to do: #1 The firearm must be registered with the BATF. #2 get a signature from your county Sheriff, or chief of police. #3 pass an extensive background check #4 receive BATF permission to move the device across state lines (getting it to you) pay a $200 transfer tax. Most importantly, you need to live in an area where the weapon you want is not outlawed, and that obviously precludes any of the above. In other w

I don't think you could seriously argue that the second amendment covers cannons, mortars, bombs, and landmines."The right of the people to keep and bear arms." implies personal firearms.... not the sort that would be solely used in large-scale warfare.

Landmines, on the other hand, would seem to fall into the same category as handguns, as the victim more often than not has no idea that his opponent is armed, or that he's even in danger. I fail to see a reason for those to exist.

Exactly specifically WHAT EXAMPLE OF "government ceasing to act in the interests of the general populace" are you all waiting for?

Until people see more serious effects in their daily lives, they'll mostly continue to be apathetic. Thanks to deficit spending, the war doesn't really even affect our tax liability, and given the small number of casualties, relatively few people know someone who has died over there.

Thus, most people are too busy living their lives to care enough to even put much time into fighting it, much less risk their lives.

Landmines by themselves will usually kill only wandering civilians and stray dogs. The enemy is clever enough to figure out that landmines exist and might be planted somewhere, and as soon as they discover a minefield they'll find a way to avoid being killed by it.

Landmines, in conjunction with other defenses, are extremely effective. For example, if the North Korean army were to swarm south across the DMZ, they would come under heavy machinegun fire, and would lack the time and ability to safely go throug

"Now do you understand the reason for landmines to exist"
As long as kids and farmers will keep loosing limbs or worse in past conflict zones, no I won't understand. It's not because in one case they are used in a well defined DMZ that their existence is justified.

I do think any nation that lays mines has a responsibility to pick them up after they're no longer used. The solution to that problem is not for landmines not to exist, but for them to be used responsibly--any weapon of war can be used irresponsibly.

I do think any nation that lays mines has a responsibility to pick them up after they're no longer used. The solution to that problem is not for landmines not to exist, but for them to be used responsibly--any weapon of war can be used irresponsibly.

Another solution would be not to sell them to people who won't use them responsibly. But that would ruin quarterly results.

I don't know much about the landmine market (do you?) but landmines are one of the easiest weapons to manufacture. This is the main reason why banning landmines accomplishes nothing: any rogue state can easily make their own.

" The Python has the ability to clear a much longer safe' lane than its predecessor. It is also faster to bring into action and far more accurate. It can clear a path up to 230m long and 7m wide through which vehicles can then safely pass.

The system works by firing a single rocket from a newly designed launcher mounted on a trailer which has been towed to the edge of the mined

Well, first you actually have to have such a vehicle, second, even if you have one a minefield forces you to waste resources using it, and third, you're still forced into a 7m wide channel instead of being able to roam widely across the entire field.

Landmines, on the other hand, would seem to fall into the same category as handguns, as the victim more often than not has no idea that his opponent is armed, or that he's even in danger. I fail to see a reason for those to exist.

Try living right next to Stalinist/Soviet/Putinist Russia for a while and the idea of putting booby traps between them and you starts getting a certain appeal.

"If premiums were to be given to merchants, to build and employ in their
service ships mounted with twenty, thirty, forty or fifty guns,
(the premiums to be in proportion to the loss of bulk to the merchants)
fifty or sixty of those ships, with a few guardships on constant duty,
would keep up a sufficient navy, and that without burdening

Though I am of the opinion that 'it was a different historical context' is a flawed argument for constitutional interpretation, there are more practical implications in this case. Basically either some weapons can be restricted, or no weapons can be restricted. If no weapons can be restricted then anyone should be able to own nuclear weapons, chemical weapons, biological weapons, shit, whatever you want. Because otherwise the logic breaks down and the argument is no longer internally consistent. Or, some

Personally, I think it was in a different historical context, but the appropriate response is not reinterpretation of the constitution but amendment, for which there is a proper procedure. I think the US constitution (2nd amendment) is fairly clear and in the context of the revolution seems to mean full military armament. Taken in the context of a world in which nuclear weapons etc exist, I do not think this is a good idea. However, if the constitution is reinterpreted according to every change in technolog

Sure it is easier with more advanced weapons, but that makes people equal, rather than the weak being subject to the violence of the strong.

This is the best argument for having a gun. I'm a trained martial artist. I have friends who train using swords and all kinds of "old school" weapons like swords and knives.

In a world without guns, I can come into a home and kill people with impunity. Even with my bare hands it is easy to a) get into a home, b) access every part of a home (have you ever tried kicking down an inside door? it's easy!) c) kill everyone in it.

Sure, the cops may have guns, but by the time they get to a house, I'd have killed ev

The world where criminals who train to fight can break into your home and kill you with no effort if you're not a trained fighter, or the one where everyone has a gun and you have a good chance of both deterring a conflict AND protecting yourself even if you're a fat computer nerd with aspergers?

The world in which I have a gun and the criminal doesn't. That's what you are describing anyway.

Where we draw the line between personal nuclear arms and total weapons bans is not the point as I see it. The point is that the government is supposed to be regulated/limited by the constitution. Where the government is freed to reinterpret the constitution at will this is no longer the case and political liberty is effectively over. Under such a system, you no longer have rights in any real sense, you have priveleges granted or revoked by the government.

Personally, I think it was in a different historical context, but the appropriate response is not reinterpretation of the constitution but amendment, for which there is a proper procedure.

I agree wholeheartedly. The problem is that at this point, laws limiting gun ownership being left to stand as constitutionally sound isnt reinterpretation, its the standing interpretation. Thus begins the debate between the Plain Words Doctrine folks and those who favor judicial review and the dominance of precedent. Its a mess, and I find neither the gun-nuts nor the anti-gun-nuts to be entirely logical on the subject.

It is two separate points being (1) It is silly to fear inanimate objects, and (2) prohibition of firearms does not prevent murder or mass murder. Point (2) is not opinion, it is demonstrable fact. Sure it is easier with more advanced weapons, but that makes people equal, rather than the weak being subject to the violence of the strong.

Ok, that makes more sense. (1) people fear silly things all the time and are otherwi

People knowingly living with irrational fear have no valid case to introduce legislation on the subject of their fear.

We're not talking about an agoraphobe introducing legislation to ban crowds. I listed several irrational fears of things that one may also rationally be wary of. I should have been more consistent in the second part of my first post. I do not have a fear of guns, that was GP. I have a rational wariness and healthy respect for devices created solely for the purpose of killing. Your statement that this is irrational is an empty statement of opinion. I dont mean to be a dick about this point, really, but I

Are you any more dead from an A-10 minigun than a 22 pistol? If you expect either you can get to safety behind sandbags. If you don't expect trouble, either can kill you in an instant.However, if the national guard rolled tanks into town because of anti-war protests and started illegally detaining and torturing protesters, that minigun would potentially be a lot more useful.

Look at the DC sniper... They used a.223 rifle, not something big and 'dangerous'. People are soft. Knives kill people. Worrying about

I disagree with your assumption that the 2nd amendment is predicated on arming the populace to resist government tyranny. The in the modern context, the well-regulated militia is the national guard. Whether or not a minigun would be handy to have around if we were suddenly thrust even further in to a police-state, I dont feel its ownership is a constitutional right.My point was simply that nobody in their right mind would defend ownership of nuclear arms as a constitutional right, so there must be a line i

You honestly believe that a branch of the government-run armed forces is the intended protection against an abusive government?Doesn't that sound silly?

As for allowing people to have nuclear weapons, I don't see how making guns illegal has gotten rid of them, or how all the campaigning against nukes has stopped countries from trying. If we make them illegal they'll still make them, but we won't know. Making them will only get easier. Controlling radioactive materials would help prevent it, but ignores the *

You honestly believe that a branch of the government-run armed forces is the intended protection against an abusive government?
Doesn't that sound silly?

I'm not saying anything of the kind. Nowhere in the 2nd amendment is any manner of language regarding protection against government tyranny. A well regulated militia, being necessary to the security of a free state has nothing the fuck to do with armed resistance of the government. Clearly, the national guard is not 'the intended protection' against abusive government, as it is in fact part of the government. The revolution was necessary because of both abusive government *and* the lack of an internal

If you think that owning a nuclear warhead is justified by their presence in the U.S. military arsenal, then I really have nothing more to say to you. Get some perspective and rejoin the discussion when you're capable of something deeper than meaningless polemic.

You lack the ability to turn printed words into the correct ideas - you then project your incorrect ideas onto other people and then attack them. Truly, it is you who should pay more attention to avoid being ignorant. Moreover, your tendency to dismiss people when they appear to disagree with you is childish.

I didn't say that I don't care if nukes get proliferated, just that I don't think passing a law will help. Can you see the type of person or group that wants a nuke stopping because California has a la

I don't think you could seriously argue that the second amendment covers cannons, mortars, bombs, and landmines.

Please don't jump to conclusions that I never stated. I never claimed that people should be able to own landmines or bombs; The GP stated that the 2nd ammendment was from the "age of muzzle loaders" (personal weapons), and then compared that to nuclear warheads (state of the art military weapons). My point was that the founding fathers were aware of a lot more weaponry than he is representing, and thus were more informed than he was representing.

Who says? The government? Isn't the constitution to be used to protect us from such laws by the government?

Of course the scare about nuclear anything is going to be a major problem when argued before certain human judges and you almost can't legally procure the materials (although it is possible) but I don't think you should be held back from making your own nuclear weapons as long as you use them to protect yourself on your own grounds. If your neighbor should be affected then it becomes a problem.

Uhm, in the US, neither the Constitution nor government "grant" rights; they eixst and are the people's independent of either. The people give the government certain powers; and we can argue what those are and how broad they are, but that's different than teh people's rights.

The constitution enumerates rights. It says as much in the 9th amendment I believe. Your right in conceptual context though, but the enumeration extends these rights to people who don't believe they have them. This is significant because if I am educated in a way that I believe the government can limit my speech and then comes along the first amendment, it was given a right I didn't know I had.This is a big cause of the confusion between the constitution giving rights and you having them with the constituti

The constitution enumerates rights. It says as much in the 9th amendment I believe. Your right in conceptual context though, but the enumeration extends these rights to people who don't believe they have them. This is significant because if I am educated in a way that I believe the government can limit my speech and then comes along the first amendment, it was given a right I didn't know I had.

I believe we are in agreement here, my concern was with the parent's "government granting..." statement. Enumerati

I don't think we are in disagreement, I was attempting to offer the "this is why people think that way" answer.

A private company has a different relationship - a contractual one that you and the company are free to define and end at will; within certain limits. In addition, there are property rights at play as well - a private entity has the right to decide not to allow firearms or limit speech on its property - whether a company or person.

It's a trebuchet, as can clearly be seen from the sling which holds the bowling balls. It also does not have an optimal sling length, but that just makes the robot itself all the more impressive.

A trebuchet is powered by a counterweight, this thing is powered by some sort of mechanical actuators meaning that it certainly is not a trebuchet. As for slings, the Roman onager used slings despite being driven by torsion rather than counterweights. Of course back then a catapult was defined as a sinew torsion based crossbow that that fired a spear. A ballista was similar but fired rocks instead, though these days we call an onager a catapult, a catapult a ballista and don't really have a name for a ballista.

A trebuchet is powered by a counterweight, this thing is powered by some sort of mechanical actuators meaning that it certainly is not a trebuchet. As for slings, the Roman onager used slings despite being driven by torsion rather than counterweights. Of course back then a catapult was defined as a sinew torsion based crossbow that that fired a spear. A ballista was similar but fired rocks instead, though these days we call an onager a catapult, a catapult a ballista and don't really have a name for a ballista.

There were non-counterweight trebuchets as well, called "traction" trebuchets. Instead of a counterweight you had a number of people tugging on ropes. I had one based on this model built for me for SCA combat as the result of a siege engine competition (Stormhold) some years ago. 60-90 metre throws with a cargo of softballs was customary with a 6 metre composite rattan arm. One advantage of a traction trebuchet is it's more mobile as you don't need to score or drag a tonne or so of counterweight along to the launch site.

So to stay on topic, I think you could call the robot arm a form of trebuchet. I've not seen onagers with slings in my researches though, will look for that. Onagers btw were so named because of the bucking motion they make, mitigated by curved ends of their foundation rails. Onager = Donkey in Latin. They were also called "rocking donkeys".

And another name for Ballista could be "ZOMG Look at the size of that effing crossbow!". They didn't always use rocks, some of them used mucking great iron bolts.

What categorizes a trebuchet as a trebuchet is the counterweight (not the sling). The qualifying factor for the catapult is the stored tension.
This has neither.
Sling or not, it's a robot, not a trebuchet or catapult.

I bought a reciprocal saw the other day at Home Depot. One of the saws' outside packaging was missing - it was a return, but it as the only DeWalt left. I asked the store clerk to open it (it had anti-theft a lock on the handle) so I could make sure all the parts were there. Upon inspection I found that the instructions, and saw blades were missing and the saw itself was extremely dirty and had a gash on the front hole where the saw blade attaches. Some asshole had bought it, used it on a job and then retu

Let me get this straight... they "Rented" the camera by buying it at Fry's and returning it?

I'm sure some people will defend this tactic, but its stuff like this that causes awesome return policies at stores to be restricted, and prices to go up. (as recently happened at CostCo)

Yeah, I was pissed at them when I read this too. I hope that when Fry institutes a 20% open-box charge on returns, that everybody look this guy up and send him a thank you note. Wrapped around a bowling ball.

Okay, I have to admit, we felt pretty bad about this "renting" tactic until we actually tried the camera. It was hands-down the worst HD camera I have ever used. I mean seriously, it had all sorts of proprietary software with weird codecs so that the footage was extremely difficult to transcode at high resolution.

I felt absolutely no remorse returning that thing. I know, that still doesn't make it right, because we didn't know that going into it. But I hope it is at least a mitigating factor. Plus, I give Fry's tons of (non-"rented") business, and their awesome return policy is a big part of the reason.

Our budget was $1K to get this all done and a great deal of that hinged on the resources we had available between the three of us. Our camera loan fell through last minute (literally) and we did not have time to research the purchase of a new one. If the cam was good we would have kept it, but it really was a piece of crap. We are about as far from trust-fund kids as you can get and that was not my first or last Fry's return for a piece of disappointing hardware.

Watching the videos, they have a rather large generator, a boom forklift, the robot, the robot power controller, a pile of bowling balls, and an RV "target." There's serious money here; planning too. They didn't just boogey out into the desert after drinking a few beers one weekend. I fail to understand how they couldn't "budget" for a camcorder... maybe borrow one from the neighbor or yell upstairs and ask to borrow mom's?

What, they needed the HD camera to make their YouTube posting look better?

This is VERY common at Fry. They have a libral return policy that is NOT likely to change. The return policy is the main reason many people put up with shopping there. The place is a mess and staffed with people who don't know anything about the products being sold. But everyone knows that it they don't like whatever they bought they can just bring it back within 30 days no questions asked.
My brother worked in IT for some company and they wanted to buy vidio cards for their computers. So he goes to F

Yes, but it is a prototype made with off the shelf components. Scale the motors up 20x and give it a hopper capable of holding a couple thousand incendiary bowling balls and it would be a lot more impressive.

Naah. World records for hammer throw (~16lb) are in the range of 260ft. A strong human could easily do it. The thing is, this will throw it exactly where you want it to go, software controllable. That's not as easy of a task for a human.

Because honestly, for what that arm was, it could have fired alot further than they had it going. I built a floating arm trebuchet 2 years back for my high school senior project and it had a least twice the range of that arm.( It could fire a half gallon of water about 250 feet. )I admit, that may have been less weight than their arm was firing, but that was because I only had about 300 pounds of counterweight. Their problem is in the release time, and the sling could stand to be a bit longer. Its still pr

They said they had some trouble determining the optimal movement of all the motors for maximum range. iirc, when trying to accelerate something, a 'whiplike" motion is preferred, similar to how a pitcher throws a fastball.

I used to work for an industrial robot company. I worked on the big arms that carried spot-welding guns around, mostly for the auto industry. Those arms were strong - there was one case where the gun welded itself to the truck frame it was building (as will happen if you don't clean the tips enough) and the robot kept right on going, and ended up tossing a truck body into the aisle when it returned to rest. Thankfully, no one was hurt.

But that incident, among others, spurred work to develop collision detection. They finally got some software running on the DSPs that'd estimate what the current to the motors should be, and measure what it actually was; too big a difference and the robot would halt. And then comes the fun part...

I got to test it.

For six months, my paid job was to take huge industrial robots and bang them into things.

I'm pure software now, and it's fun and pays better... but I still think about those days with fondness.

Haha, Dodged a few castings from a DCpress recently. Rejected a bad cast and the arm just shook it in the air and tossed it across the floor at my feet. The operator had to reset it a few times. I swear it was mocking me.

In the floorpan line of a well-known auto manufacturer, the safety folks wanted to test the OSHA safe stopping distance calculation used to place some light curtains.

The way you protect workers from getting killed by a robot (and these things are way stronger than you think, even after seeing it fling rocks) is to put up light curtains around the robot.
The OSHA safe stopping distance calculation is used to prove that the hazardous motion will stop in the time it takes the person to traverse the light curtain and come into contact with the equipment.

So, the safety folks find the robot with the biggest, fastest moving load on the line--the floorpan skin transfer robot.
A floorpan skin is basically a sixty-pound razor blade.
The end effector held onto the floorpan skin with suction cups, which are a cost-effective and reliable method for the process.

The robot guys set up a test, where they got all 6 axes of the robot moving in such a manner that the end effector achieved its maximum possible speed. Not something you'd normally do, but a worst-case scenario for use as safety systems challenge.
We all wanted to see this robot haul ass, so the safety folks had us all standing back...
Robot dude picked up the TP and initiated the path at 100% speed...
Somebody waited for the arm to get to full extension and speed...and stuck their hand into the light curtain.

The robot stopped almost instantly--well within the expected stopping distance. No way that person would have been injured by the robot.